Press into prepared pan, on bottom and up sides to form crust.
Saute onion in bacon drippings.
Add sausage and/or ground beef and brown.
Drain thoroughly, blot with paper towel.
Spread meat and onion over crust.
Mix eggs with milk and pour over meat.
Top with mushrooms and jalapenos, if desired.
Spread cheese over top of all.
Bake until eggs are set and cheese is melted